A prospective randomised study comparing TightRope and syndesmotic screw fixation for accuracy and maintenance of syndesmotic reduction assessed with bilateral computed tomography
Introduction
The classic presentation of syndesmotic disruption occurs in addition to Lauge-Hansen pronation-external rotation (PER) Danis-Weber type C ankle fracture [1], [2]. Malreduction of the syndesmosis that alters tibiofibular joint kinematics is reported to impair ankle function and lead to early osteoarthritis [3], [4], [5]. Therefore, accuracy and maintenance of reduction of the syndesmosis are considered essential when treating ankle fractures with concomitant syndesmosis injury [4], [6], [7], [8], [9].
Metallic trans-syndesmotic screw has been the most popular fixation method to stabilise unstable syndesmosis [10], [11], [12]. However, syndesmosis malreduction is reported to occur up to more than 50% in syndesmotic screw fixation [13], [14], [15], [16], [17], [18]. A further problem with syndesmosis screws is the potential late diastasis due to screw breakage or screw removal [13], [17], [19], [20].
Flexible TightRope® (Arthrex, Naples, FL, USA) suture-button device was developed for physiologic stabilisation of the ankle mortise; its use has increased rapidly over the last years [21]. Theoretically, this suture-button device allows physiologic motion of the syndesmosis without need for implant removal, which may lower the risk of recurrent syndesmotic diastasis as described after syndesmosis screw removal [11]. Biomechanical investigations have demonstrated that the strength of TightRope device is comparable to a tricortical 3.5 mm syndesmotic screw [22], [23], [24]. Several recent studies assessed syndesmosis stabilisation with suture-button device [25], [26], [27], [28], [29] and comparative studies reported at least as good functional results with this device in comparison to syndesmotic screw [18], [30], [31], [32], [33]. Previously the rate of syndesmosis malreduction associated with suture-button device ranged from 0% to 11% [18], [25], [29], [30], [33], [34].
The majority of earlier studies of syndesmosis fixation used only plain radiographs to assess syndesmosis reduction [8], [13], [25], [26], [29], [30], [35], [36], [37], [38]. Intra-operative fluoroscopy and post-operative conventional radiography are currently considered inaccurate to assess syndesmosis reduction; [14], [17], [18], [39] computer tomography (CT) of both ankles is recommended [17], [18], [40], [41], [42], [43], [44], [45].
Only a few published clinical studies with functional results have assessed syndesmotic reduction with bilateral CT, [16], [17], [18] and none of them has used both intra-operative and follow-up CT for assessing syndesmosis reduction. Furthermore, only two prospective randomised controlled trial has compared screw and TightRope for syndesmosis fixation [32], [33].
The primary purpose of this prospective randomised trial comparing fixation via syndesmosis screw or TightRope was to assess the accuracy and the maintenance of syndesmosis reduction using bilateral CT. The secondary purpose was to compare functional outcome and the rate of OA after at least 2 years of follow-up. Based on previous literature, we hypothesised that the malreduction rate of screw fixation would be 50%, and the malreduction rate of TightRope fixation would be 5%.
Section snippets
Study design
We conducted a prospective randomised trial (ClinicalTrials.gov, NCT01742650) comparing fixation via TightRope® or via one 3.5-mm tricortical trans-syndesmotic screw for the treatment of syndesmosis injury in Lauge-Hansen pronation-external rotation-type ankle fractures. CONSORT-guidelines were followed (http://www.consort-statement.org). The ethical committee of our hospital approved the study protocol.
Study population
All skeletally mature patients (16 years or older) who visited emergency department of an
Results
Baseline characteristics of the patients are shown in Table 1.
Discussion
The present prospective randomised trial showed that syndesmotic screw and TightRope fixation resulted in a low malreduction rate (5%) and both methods maintained reduction well (syndesmotic screw 84% and TightRope 95%). However, intraoperative CT scanning was unreliable when assessing TightRope fixation, and false positive findings were common. Therefore, the value of intraoperative CT scanning may be questioned and open exploration may be a better technique than CT to confirm syndesmosis
Conclusion
Syndesmotic screw and TightRope fixation had similar postoperative malreduction rates in patients with pronation-external rotation, Weber C-type ankle fracture and associated syndesmosis injury. Intraoperative CT scanning of the ankles with TightRope fixation can be misleading due to dynamic nature of the fixation, unless scanning technique is meticulous with the ankle supported in 90 degrees’ angle. After at least 2 years of follow-up, analysis of bilateral CBCT data suggested that the rate of
Funding
The study was supported by Oulu University Central Hospital. The funding source had no influence or involvement in the study.
Conflict of interest
Medical Physicist, PhD Jani Katisko has a consultant service agreement with Medtronic Finland Oy. All other authors declare that they have no financial or personal relationships that could influence this study.
References (61)
- et al.
An anatomical way of treating ankle syndesmotic injuries
J Foot Ankle Surg
(2011) - et al.
Does the Arthrex TightRope(R) provide maintenance of the distal tibiofibular syndesmosis? A 2-year follow-up of 64 TightRopes(R) in 37 patients
J Foot Ankle Surg
(2013) - et al.
TightRope fixation of ankle syndesmosis injuries: clinical outcome, complications and technique modification
Injury
(2012) - et al.
Transosseous fixation of the distal tibiofibular syndesmosis: comparison of an interosseous suture and endobutton to traditional screw fixation in 50 cases
J Foot Ankle Surg
(2009) - et al.
Malreduction of syndesmosis – are we considering the anatomical variation
Injury
(2011) - et al.
Functional outcomes following syndesmotic fixation: a comparison of screws retained in situ versus routine removal – is it really necessary
Injury
(2013) - et al.
Pain measurement: an overview
Pain
(1985) Fractures of the ankle. II. Combined experimental-surgical and experimental-roentgenologic investigations
Arch Surg
(1950)Die Verletzungen Des Oberen Sprunggelenkes
Aktuelle Probleme in Der Chirurgie
(1972)- et al.
Quantitative criteria for prediction of the results after displaced fracture of the ankle
J Bone Joint Surg Am
(1983)
Instability of the distal tibiofibular syndesmosis after bimalleolar and trimalleolar ankle fractures
J Bone Joint Surg Am
Operative treatment of ankle fracture-dislocations. A follow-up study of 306/321 consecutive cases
Clin Orthop Relat Res
Changes in tibiotalar area of contact caused by lateral talar shift
J Bone Joint Surg Am
Mechanical considerations for the syndesmosis screw. A cadaver study
J Bone Joint Surg Am
The influence of a diastasis screw on the outcome of Weber type-C ankle fractures
J Bone Joint Surg Br
The tibiofibular syndesmosis. Evaluation of the ligamentous structures, methods of fixation, and radiographic assessment
J Bone Joint Surg Am
Current concepts review: operative techniques for stabilizing the distal tibiofibular syndesmosis
Foot Ankle Int
Acute distal tibiofibular syndesmosis injury: a systematic review of suture-button versus syndesmotic screw repair
Int Orthop
Injuries to the ankle syndesmosis
J Bone Joint Surg Am
Predictors of functional outcome following transsyndesmotic screw fixation of ankle fractures
J Orthop Trauma
Malreduction of the tibiofibular syndesmosis in ankle fractures
Foot Ankle Int
Direct visualization for syndesmotic stabilization of ankle fractures
Foot Ankle Int
No difference in functional and radiographic results 8.4 years after quadricortical compared with tricortical syndesmosis fixation in ankle fractures
J Orthop Trauma
The functional consequence of syndesmotic joint malreduction at a minimum 2-year follow-up
J Orthop Trauma
Fixation of ankle syndesmotic injuries: comparison of TightRope fixation and syndesmotic screw fixation for accuracy of syndesmotic reduction
Am J Sports Med
Functional outcomes after syndesmotic screw fixation and removal
J Orthop Trauma
Surgical treatment of syndesmotic diastasis: emphasis on effect of syndesmotic screw on ankle function
Int Orthop
Ankle fracture syndesmosis fixation and management: the current practice of orthopedic surgeons
Am J Orthop (Belle Mead NJ)
Suture-button versus screw fixation in a syndesmosis rupture model: a biomechanical comparison
Foot Ankle Int
Suture-button versus screw fixation of the syndesmosis: a biomechanical analysis
Foot Ankle Int
Cited by (134)
High-Ankle Sprain and Syndesmotic Instability: How Far Have We Come with Diagnosis and Treatment?
2023, Foot and Ankle ClinicsWhat is the best treatment for syndesmosis fixation? Suture-button or syndesmotic screw ? Bilateral CT-based early postoperative analysis
2023, Foot and Ankle SurgeryCitation Excerpt :However, 3D systems may not be available in every clinic and it can be difficult and time-consuming to evaluate these images. In a study by Kortekangas et al., syndesmosis reduction was evaluated on bilateral intraoperative and postoperative CT imaging, and similar post-operative malreduction rates were reported for both the syndesmotic screw and suture button system [16]. In that study, posterior malleolar fractures of ≥25 % were fixed and other fractures were not operated on. However, this practice is outdated and in our clinic all fixable posterior malleolar fractures are treated surgically, which facilitates the anatomic reduction of syndesmosis [21,22].
Syndesmotic Malreduction Prevention, Assessment, and Treatment
2023, Foot and Ankle Clinics